Always bogs down going uphill on long grade

Maintenance/Repairs
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1

My pickup always bogs down going up a grade, seems like its flooding out and it starts running real rough and vibrating bad, I have to let off gas and pull over .

Been to shop several times, no one seems to know what’s causing it.

2

“Seems like it’s flooding out…” Why do you say that?

Sounds more like fuel starvation. Does it matter whether the gas tank is full or near empty? Maybe a problem with the fuel pump or the fuel pickup in the gas tank being blocked or floating loose so that when gas sloshes back it won’t suck fuel properly.

3

What year is your Chevy?

Tester

4

Age, miles, service repair history, check engine light on? Info like that can help get to the problem. When was the fuel filter replaced? I had an older Jeep that ran fine on flat or mild grades, but bucked on steep hills, turned out to be the coil (only had a single coil) it was weak and started to fail under load. Once it was replaced it ran fine.

5

‘‘always’’ ?
Is this a new problem or has it occured since the truck was new ?

Up here an my altitude ( 6500 ) you’ll get that sort of thing as a constant

6

Answering all of the above could help. Two key reasons for loss of power under load are clogged catalytic converters and failing fuel pumps. Starting there would be a no brainer for most shops - so it would also help to say what has been checked when it’s been in the shop.

7

Good comments above. I’ll add, is it pinging when this happens? If so, double check the spark plug condition and gap.

8

If it is “flooding out” you should smell gas. Can’t make a guess without year,make, model, mileage and engine.

9

no gas smell, 1998 PU 1500,276,000, V-8

10

Maybe clogged fuel filter.

11

My father in law had a problem with losing power going uphill and it didn’t have to be a long hill.

The substrate in his catalytic converter had broken and was lying loose in the converter and when he went uphill it blocked the outlet.

I don’t know if you have this type of converter but go underneath and hit the converter with a rubber mallet or the side of your fist and see if it rattles inside.

12

My vote is clogged fuel filter.